CVE-2026-126436 json
OpenEMR before 8.5.0 OAuth2 Grant Type Enforcement Bypass via Token Endpoint
published 18d ago modified yesterday also EUVD-2026-125007 , GHSA-qjj7-c4m9-6f92
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository openemr/openemr. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 33%
- public exploits
- 0
- none known
Summary
OpenEMR before 8.5.0 contains an authorization bypass vulnerability that allows OAuth2 clients to use unregistered grant types because oauth_clients.grant_types is never enforced. Attackers can request tokens with grant_type=password to bypass the user consent screen, and disabled clients can redeem authorization codes using JWT client assertions.
Patch / fix
- openemr openemr 8.5.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- yesterday
Exploit prediction
0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-14).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- openemr openemr
Classification
- Weakness
-
- CWE-862 Missing Authorization
References
-
github.com
/openemr/openemr/security/advisories/GHSA-qjj7-c4m9-6f92
vendor-advisory, advisory
-
vulncheck.com
/advisories/openemr-before-8.5.0-oauth2-grant-type-enforcement-bypass-via-token-endpoint
third-party-advisory
Sources
- CVE List CVE-2026-126436
- NVD CVE-2026-126436
- Maintainer advisory GHSA-qjj7-c4m9-6f92
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of openemr/openemr published their own advisory on GitHub. Reviewed sources take precedence over it.